diff --git a/src/modules/module-protocol-pulse/modules/module-ladspa-sink.c b/src/modules/module-protocol-pulse/modules/module-ladspa-sink.c
index 049433add..c831ba92e 100644
--- a/src/modules/module-protocol-pulse/modules/module-ladspa-sink.c
+++ b/src/modules/module-protocol-pulse/modules/module-ladspa-sink.c
@@ -215,7 +215,8 @@ static int module_ladspa_sink_prepare(struct module * const module)
 
 	if ((str = pw_properties_get(capture_props, PW_KEY_NODE_DESCRIPTION)) == NULL) {
 		str = pw_properties_get(capture_props, PW_KEY_NODE_NAME);
-		pw_properties_setf(props, PW_KEY_NODE_DESCRIPTION,
+		if (str != NULL)
+			pw_properties_setf(props, PW_KEY_NODE_DESCRIPTION,
 					"%s Sink", str);
 	} else {
 		pw_properties_set(props, PW_KEY_NODE_DESCRIPTION, str);
diff --git a/src/modules/module-protocol-pulse/modules/module-ladspa-source.c b/src/modules/module-protocol-pulse/modules/module-ladspa-source.c
index 94b3c428c..393a0124a 100644
--- a/src/modules/module-protocol-pulse/modules/module-ladspa-source.c
+++ b/src/modules/module-protocol-pulse/modules/module-ladspa-source.c
@@ -215,7 +215,8 @@ static int module_ladspa_source_prepare(struct module * const module)
 
 	if ((str = pw_properties_get(playback_props, PW_KEY_NODE_DESCRIPTION)) == NULL) {
 		str = pw_properties_get(playback_props, PW_KEY_NODE_NAME);
-		pw_properties_setf(props, PW_KEY_NODE_DESCRIPTION,
+		if (str != NULL)
+			pw_properties_setf(props, PW_KEY_NODE_DESCRIPTION,
 					"%s Source", str);
 	} else {
 		pw_properties_set(props, PW_KEY_NODE_DESCRIPTION, str);